Horsemeat expected to be found in more British ready meals

Environment secretary Owen Paterson talks to the media after an emergency meeting over the horsemeat scandal. Photograph: Will Oliver/AFP/Getty Images

More British ready meals are expected to be found to contain horsemeat over the next few weeks, the environment secretary has warned.

The warning by Owen Paterson came after he held an emergency summit with bosses from leading supermarkets and the Food Standards Agency (FSA) to tackle the scandal of horse in beef products.

Food businesses have been told to send initial test results on all their products to the FSA by Friday.

"There may well be more bad results coming through, that's the point of doing this random analysis," he said.

The minister said the scandal was either due to "gross incompetence" or an international criminal "conspiracy".

"If there's a criminal act we will work with the authorities wherever they are to ensure the appropriate measures are taken," he said. "It's a straight fraud. If a product says it's beef and you're actually buying horse, that is a fraud. It is in the interests of everyone to get this resolved as rapidly as possible.

"This is a conspiracy against the public."

Paterson said that retailers held the "ultimate responsibility" for ensuring there was no horsemeat in their products. Retailers would have to start doing their own testing, he said, noting that the supermarkets had agreed to work with the FSA to report their test results every three months.

"Ultimate responsibility for the integrity of what is sold on their label has to lie with the retailer," he said.

Representatives from Tesco, Sainsbury's, Asda, Morrisons and other groups attended the meeting at the Department for Environment, Food and Rural Affairs in London.

Paterson said the supermarkets had agreed that consumers should be compensated if they have bought withdrawn products, with no questions asked.

Asked if there were any plans to test for traces of other meats, such as dog, in ready meals, the minister said: "It may be very isolated, it might be a small number of suppliers involved in the horse trade. We don't know, but I think that as we progress, and we'll know more over the course of the next few weeks, we can decide what to do next."

Questioned about whether he would be prepared to eat meat bought from a supermarket, he said: "I would be very happy to eat any products on sale in British supermarkets this morning, but I would not recommend anyone to eat a product which has been withdrawn."

The Labour MP Tom Watson published a letter on his website which he claimed was sent by Findus to retailers on Monday, warning that a French-based supplier had told it there may be problems with raw materials delivered since 1 August last year.

In it, the firm claimed raw materials delivered to a French contractor since 1 August were "likely to be non-conform and consequently the labelling on finished products is incorrect".

The letter added: "The supplier has asked us to withdraw the raw material batches."

But Findus has denied reports that the company first knew there was horsemeat in its products last year.

"Findus want to be absolutely explicit that they were not aware of any issue of contamination with horsemeat last year," it said in a statement. "They were only made aware of a possible August 2012 date through a letter dated 2 February 2013 from the supplier Comigel. By then Findus was already conducting a full supply chain traceability review and had pro-actively initiated DNA testing."

The Metropolitan police said officers had met the FSA over the scandal, although there is currently no official police investigation.

Aldi said it felt "angry and let down" by its French supplier Comigel after tests on Today's Special frozen beef lasagne and Today's Special frozen spaghetti bolognese found they contained between 30% and 100% horsemeat.

The company added that it would test the meals for the veterinary drug phenylbutazone, often referred to as bute, but said it was confident the meals were safe.

Comigel, which also produced the contaminated Findus beef lasagnes, has blamed its suppliers. Erick Lehagre said he believed his company was buying French beef from a company called Spanghero but it had since told him it had come from Romania.

The Trading Standards Institute has said the discovery of such high levels of horse meat suggests "deliberate fraudulent activity".

Hospitals and education authorities were also checking the food they provide for traces of horsemeat.

The FSA advised consumers who had bought affected beef lines from Findus not to eat them. They had not been tested for the presence of phenylbutazone, which is banned in the human food chain. It can cause a serious blood disorder in rare cases.

The Guardian has also established that the FSA has been unable to trace all the horses slaughtered in the UK that tested positive for bute last year. The agency has routinely been testing less than 1% of slaughtered horses for the drug, but found four positives in a sample of 82 carcasses in 2012. It carried out a special additional survey on a further 63 horses last year and found 5% of those contained residues, bringing the total of positives to nine.

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